U.S. patent application number 10/596429 was filed with the patent office on 2007-05-03 for preventive agent for vasculitis.
This patent application is currently assigned to Chugai Seiyaku Kabushiki Kaisha. Invention is credited to Tadamitsu Kishimoto, Hideko Nakahara, Norihiro Nishimoto.
Application Number | 20070098714 10/596429 |
Document ID | / |
Family ID | 37996607 |
Filed Date | 2007-05-03 |
United States Patent
Application |
20070098714 |
Kind Code |
A1 |
Nishimoto; Norihiro ; et
al. |
May 3, 2007 |
Preventive agent for vasculitis
Abstract
To provide a preventive and/or therapeutic agent for vasculitis
such as polyarteritis nodosa, the aortitis syndrome, and a
vasculitis that is associated with immunological abnormalities,
said agent comprising an interleukin-6 (IL-6) antagonist as an
active ingredient.
Inventors: |
Nishimoto; Norihiro; (Osaka,
JP) ; Kishimoto; Tadamitsu; (Osaka, JP) ;
Nakahara; Hideko; (Osaka, JP) |
Correspondence
Address: |
FOLEY AND LARDNER LLP;SUITE 500
3000 K STREET NW
WASHINGTON
DC
20007
US
|
Assignee: |
Chugai Seiyaku Kabushiki
Kaisha
|
Family ID: |
37996607 |
Appl. No.: |
10/596429 |
Filed: |
December 17, 2004 |
PCT Filed: |
December 17, 2004 |
PCT NO: |
PCT/JP04/19463 |
371 Date: |
August 7, 2006 |
Current U.S.
Class: |
424/143.1 |
Current CPC
Class: |
C07K 2317/76 20130101;
A61K 2039/505 20130101; C07K 16/2866 20130101; C07K 2317/24
20130101 |
Class at
Publication: |
424/143.1 |
International
Class: |
A61K 39/395 20060101
A61K039/395 |
Claims
1. A preventive and/or therapeutic agent for vasculitis, said agent
comprising an interleukin-6 (IL-6) antagonist as an active
ingredient.
2. A preventive and/or therapeutic agent, for vasculitis having
resistance to steroids and/or immunosuppressants, said agent
comprising an interleukin-6 (IL-6) antagonist as an active
ingredient.
3. The preventive and/or therapeutic agent according to claim 1
wherein said vasculitis is polyarteritis nodosa.
4. The preventive and/or therapeutic agent according to claim 1
wherein said vasculitis is the aortitis syndrome.
5. The preventive and/or therapeutic agent according to claim 1
wherein said vasculitis is vasculitis associated with immunological
abnormalities.
6. The preventive and/or therapeutic agent according to claim 1
wherein said IL-6 antagonist is an antibody against IL-6
receptor.
7. The preventive and/or therapeutic agent according to claim 6
wherein said antibody against IL-6 receptor is a monoclonal
antibody against IL-6 receptor.
8. The preventive and/or therapeutic agent according to claim 6
wherein said antibody against IL-6 receptor is a monoclonal
antibody against human IL-6 receptor.
9. The preventive and/or therapeutic agent according to claim 6
wherein said antibody against IL-6 receptor is a monoclonal
antibody against mouse IL-6 receptor.
10. The preventive and/or therapeutic agent according to claim 6
wherein said antibody against IL-6 receptor is a recombinant
antibody.
11. The preventive and/or therapeutic agent according to claim 8
wherein said monoclonal antibody against human IL-6 receptor is
PM-1 antibody.
12. The preventive and/or therapeutic agent according to claim 9
wherein said monoclonal antibody against mouse IL-6 receptor is
MR16-1 antibody.
13. The preventive and/or therapeutic agent according to claim 6
wherein said antibody against IL-6 receptor is a chimeric antibody,
a humanized antibody, or a human antibody against IL-6
receptor.
14. The preventive and/or therapeutic agent according to claim 13
wherein said humanized antibody against mouse IL-6 receptor is
humanized PM-1 antibody.
15. The use of interleukin-6 (IL-6) antagonist for the manufacture
of a preventive and/or therapeutic agent for vasculitis.
16. The use of interleukin-6 (IL-6) antagonist for the manufacture
of a preventive and/or therapeutic agent for vasculitis having
resistance to steroids and/or immunosuppressants.
17. The use according to claim 15 wherein said vasculitis is
polyarteritis nodosa.
18. The use according to claim 15 wherein said vasculitis is the
aortitis syndrome.
19. The use according to claim 15 wherein said vasculitis is
vasculitis associated with immunological abnormalities.
20. The use according to claim 15 wherein said IL-6 antagonist is
an antibody against IL-6 receptor.
21. The use according to claim 20 wherein said antibody against
IL-6 receptor is a monoclonal antibody against IL-6 receptor.
22. The use according to claim 20 wherein said antibody against
IL-6 receptor is a monoclonal antibody against human IL-6
receptor.
23. The use according to claim 20 wherein said antibody against
IL-6 receptor is a monoclonal antibody against mouse IL-6
receptor.
24. The use according to claim 20 wherein said antibody against
IL-6 receptor is a recombinant antibody.
25. The use according to claim 22 wherein said monoclonal antibody
against human IL-6 receptor is PM-1 antibody.
26. The use according to claim 23 wherein said monoclonal antibody
against mouse IL-6 receptor is MR16-1 antibody.
27. The use according to claim 20 wherein said antibody against
IL-6 receptor is a chimeric antibody, a humanized antibody, or a
human antibody.
28. The use according to claim 27 wherein said humanized antibody
against IL-6 receptor is a humanized PM-1 antibody.
29. A method of preventing and/or treating vasculitis comprising
administering an interleukin-6 (IL-6) antagonist to a subject in
need thereof.
30. A method of preventing and/or treating vasculitis having
resistance to steroids and/or immunosuppressants, comprising
administering an interleukin-6 (IL-6) antagonist to a subject in
need thereof.
31. The method according to claim 29 wherein said vasculitis is
polyarteritis nodosa.
32. The method according to claim 29 wherein said vasculitis is the
aortitis syndrome.
33. The method according to claim 29 wherein said vasculitis is
vasculitis associated with immunological abnormalities.
34. The method according to claim 29 wherein said IL-6 antagonist
is an antibody against IL-6 receptor.
35. The method according to claim 34 wherein said antibody against
IL-6 receptor is a monoclonal antibody against IL-6 receptor.
36. The method according to claim 34 wherein said antibody against
IL-6 receptor is a monoclonal antibody against human IL-6
receptor.
37. The method according to claim 34 wherein said antibody against
IL-6 receptor is a monoclonal antibody against mouse IL-6
receptor.
38. The method according to claim 34 wherein said antibody against
IL-6 receptor is a recombinant antibody.
39. The method according to claim 36 wherein said monoclonal
antibody against human 1'-6 receptor is PM-1 antibody.
40. The method according to claim 37 wherein said monoclonal
antibody against mouse IL-6 receptor is MR1 antibody.
41. The method according to claim 34 wherein said antibody against
IL-6 receptor is a chimeric antibody, humanized antibody, or a
human antibody against IL-6 receptor.
42. The method according to claim 41 wherein said humanized
antibody against IL-6 receptor is a humanized PM-1 antibody.
Description
TECHNICAL FIELD
[0001] The present invention relates to a novel preventive and/or
therapeutic agent for vasculitis.
BACKGROUND ART
[0002] Vasculitis is one of the intractable pathological conditions
commonly observed in autoimmune diseases, and many cases thereof
are refractory to conventionally-used therapeutic methods such as
steroids and immunosuppressants and, therefore, new therapeutic
methods have been sought. In the vasculitis syndrome, inflammation
occurs in arteries of various sizes, and fever, pain in muscles and
joints, vascular occlusion, skin ulcer, and mononeuritis multiplex
may develop. Vasculitis includes intractable vasculitis syndromes
such as polyarteritis nodosa and the aortitis syndrome. Lesions of
polyarteritis nodosa are characterized by necrotic inflammations of
the media and the adventitia, and aortitis usually develops
inflammations of the intima, the media and the adventitia.
[0003] Aortitis is also called Takayasu's arteritis. The pathology
of vasculitis has been suggested to be associated with IL-6. For
example, Noris et al. have reported that blood levels of IL-6 are
increased in patients with Takayasu's arteritis in the active stage
of pathology compared to normal healthy people (Circulation 1999
Jul. 6; 100 (1); 55-60). However, this paper also reports that the
serum concentration of RANTES, one of the kemokines, is also
enhanced. Noris et al. also suggest the possibility that these
cytokines are responsible for vasculitic lesions in patients with
Takayasu's arteritis.
DISCLOSURE OF THE INVENTION
[0004] The paper, however, does not make any mention of the
possibility that Takayasu's arteritis can be treated by inhibiting
IL-6. Thus, the present invention provides a preventive and/or
therapeutic agents for vasculitis comprising an IL-6 antagonist as
an active ingredient.
[0005] After intensive and extensive research, the present
inventors have demonstrated that IL-6 is indispensable in the
pathology of vasculitis and that an IL-6 antagonist has a
therapeutic effect for vasculitis. More surprisingly, in the study
by the present inventors, when the binding of IL-6 to its receptor
was inhibited by an IL-6 receptor antibody IL-6 per se was
decreased in the blood. Thus, it was demonstrated that the IL-6
inhibition therapy not only has an anti-inflammatory effect on
vasculitis per se but also treats vasculitis per se by acting on
the core of vasculitis.
[0006] Thus, the present invention provides a preventive and/or
therapeutic agent for vasculitis, said agent comprising an
interleukin-6 (IL-6) antagonist as an active ingredient.
[0007] The present invention provides a preventive and/or
therapeutic agent for vasculitis having resistance to steroids
and/or immunosuppressants, said agent comprising an interleukin-6
(IL-6) antagonist as an active ingredient.
[0008] Said vasculitis is for example polyarteritis nodosa, the
aortitis syndrome, or a vasculitis that is associated with
immunological abnormalities. The aortitis syndrome is also termed
as Takayasu's arteritis. As vasculitis associated with
immunological abnormalities, for example, there can be mentioned
vasculitis associated with rheumatoid and vasculitis associated
with systemic lupus erythematosus (SLE).
[0009] Said IL-6 antagonist is, for example, an antibody against
IL-6 or an antibody against IL-6 receptor, preferably a monoclonal
antibody against IL-6 receptor. Said antibody against IL-6 receptor
is most preferably a monoclonal antibody against human IL-6
receptor, for example PM-1 antibody, or a monoclonal antibody
against mouse IL-6 receptor, for example MR16-1 antibody. Said
antibody against IL-6 receptor is preferably a recombinant
antibody.
[0010] Said antibody against IL-6 receptor can be a chimeric
antibody, humanized antibody, or human antibody. As used herein the
most preferably antibody is a humanized PM-1 antibody.
[0011] The present invention can also have the following
aspects:
[0012] (1) The use of interleukin-6 (IL-6) antagonist for the
manufacture of a preventive and/or therapeutic agent for
vasculitis.
[0013] (2) The use of interleukin-6 (IL-6) antagonist for the
manufacture of a preventive and/or therapeutic agent for vasculitis
having resistance to steroids and/or immunosuppressants.
[0014] (3) The use according to the above (1) or (2) wherein said
vasculitis is polyarteritis nodosa.
[0015] (4) The use according to the above (1) or (2) wherein said
vasculitis is the aortitis syndrome.
[0016] (5) The use according to the above (1) or (2) wherein said
vasculitis is vasculitis associated with immunological
abnormalities.
[0017] (6) The use according to any of the above (1) to (5) wherein
said IL-6 antagonist is an antibody against IL-6 receptor.
[0018] (7) The use according to the above (6) wherein said antibody
against IL-6 receptor is a monoclonal antibody against IL-6
receptor.
[0019] (8) The use according to the above (6) wherein said antibody
against IL-6 receptor is a monoclonal antibody against human IL-6
receptor.
[0020] (9) The use according to the above (6) wherein said antibody
against IL-6 receptor is a monoclonal antibody against mouse IL-6
receptor.
[0021] (10) The use according to any of the above (6) to (9)
wherein said antibody against IL-6 receptor is a recombinant
antibody.
[0022] (11) The use according to the above (8) wherein said
monoclonal antibody against human IL-6 receptor is PM-1
antibody.
[0023] (12) The use according to the above (9) wherein said
monoclonal antibody against mouse IL-6 receptor is MR16-1
antibody.
[0024] (13) The use according to any of the above (6) to (12)
wherein said antibody against IL-6 receptor is a chimeric antibody,
a humanized antibody, or a human antibody.
[0025] (14) The use according to the above (13) wherein said
humanized antibody against IL-6 receptor is a humanized PM-1
antibody.
[0026] (15) A method of preventing and/or treating vasculitis
comprising administering an interleukin-6 (IL-6) antagonist.
[0027] (16) A method of preventing and/or treating vasculitis
having resistance to steroids and/or immunosuppressants comprising
administering an interleukin-6 (IL-6) antagonist.
[0028] (17) The method according to the above (15) or (16) wherein
said vasculitis is polyarteritis nodosa.
[0029] (18) The method according to the above (15) or (16) wherein
said vasculitis is the aortitis syndrome.
[0030] (19) The method according to the above (15) or (16) wherein
said vasculitis is vasculitis associated with immunological
abnormalities.
[0031] (20) The method according to any of the above (15) to (19)
wherein said IL-6 antagonist is an antibody against IL-6
receptor.
[0032] (21) The method according to the above (20) wherein said
antibody against IL-6 receptor is a monoclonal antibody against
IL-6 receptor.
[0033] (22) The method according to the above (20) wherein said
antibody against IL-6 receptor is a monoclonal antibody against
human IL-6 receptor.
[0034] (23) The method according to the above (20) wherein said
antibody against IL-6 receptor is a monoclonal antibody against
mouse IL-6 receptor.
[0035] (24) The method according to any of the above (20) to (23)
wherein said antibody against IL-6 receptor is a recombinant
antibody.
[0036] (25) The method according to the above (22) wherein said
monoclonal antibody against human IL-6 receptor is PM-1
antibody.
[0037] (26) The method according to the above (23) wherein said
monoclonal antibody against mouse IL-6 receptor is MR1
antibody.
[0038] (27) The method according to any of the above (20) to (26)
wherein said antibody against IL-6 receptor is a chimeric antibody,
humanized antibody, or a human antibody against IL-6 receptor.
[0039] (28) The method according to the above (27) wherein said
humanized antibody against IL-6 receptor is a humanized PM-1
antibody.
BRIEF EXPLANATION OF THE DRAWINGS
[0040] FIG. 1 is a photograph showing the result of CT in the
treatment of the vasculitis syndrome with humanized IL-6R antibody,
in which the upper arrow indicates the ascending aorta and the
lower arrow indicates the descending aorta
[0041] FIG. 2 is a photograph showing the result of CT in the
treatment of the vasculitis syndrome with humanized IL-6R antibody,
in which the arrow indicates the aortic arch.
[0042] FIG. 3 is a photograph showing the result of CT in the
treatment of the vasculitis syndrome with humanized IL-6R antibody,
in which the upper arrow indicates the ascending aorta and the
lower arrow indicates the descending aorta
[0043] FIG. 4 is a photograph showing the result of CT in the
treatment of the vasculitis syndrome with humanized IL-6R antibody,
in which the upper arrow indicates the ascending aorta and the
lower arrow indicates the descending aorta
[0044] FIG. 5 is a photograph showing the result of CT in the
treatment of the vasculitis syndrome with humanized IL-6R antibody,
in which the arrow indicates the aortic arch.
[0045] FIG. 6 is a photograph showing the result of CT in the
treatment of the vasculitis syndrome with humanized IL-6R antibody,
in which the upper arrow indicates the ascending aorta and the
lower arrow indicates the descending aorta
BEST MODE FOR CARRYING OUT THE INVENTION
[0046] IL-6 is a cytokine which is also called B cell stimulating
factor 2 (BSF2) or interleukin .beta.2. IL-6 was discovered as a
differentiation factor involved in the activation of B-lymphatic
cells (Hirano, T. et al., Nature (1986) 324, 73-76). Thereafter, it
was found to be a multifunctional cytokine that influences various
functions of cells (Akira, S. et al., Adv. in Immunology (1993) 54,
1-78). IL-6 has been reported to induce the maturation of
T-lymphatic cells (Lotz, M. et al., J. Exp. Med. (1988) 167,
1253-1258).
[0047] IL-6 transmits its biological activity through two types of
proteins on the cell. One of them is IL-6 receptor, a ligand-biding
protein with a molecular weight of about 80 kD, to which IL-6 binds
(Taga, T. et al., J. Exp. Med. (1987) 166, 967-9381; Yamasaki, K.
et al., Science (1987) 241, 825-828). IL-6 receptor occurs not only
in the membrane-bound form that penetrates through and is expressed
on the cell membrane but also as a soluble IL-6 receptor consisting
mainly of the extracellular region.
[0048] The other is a membrane-bound protein gp130 having a
molecular weight of about 130 kD that is involved in
non-ligand-binding signal transduction. IL-6 and IL-6 receptor form
the IL-6/IL-6 receptor complex which, after binding to gp130,
transmits its biological activity to the cell (Taga, T. et al.,
Cell (1989) 58, 573-581).
[0049] An IL-6 antagonist is a substance that inhibits the
transduction of biological activity of IL-6. As the IL-6
antagonist, there have been known so far antibody directed against
IL-6 (anti-IL-6 antibody), antibody directed against IL-6 receptor
(anti-IL-6 receptor antibody), and antibody directed against gp130
(anti-gp130 antibody), altered IL-6, partial peptides of IL-6 or
IL-6 receptor and the like.
[0050] Anti-IL-6 receptor antibody has been described in several
reports (Novick D. et al., Hybridoma (1991) 10, 137-146, Huang, Y.
W. et al., Hybridoma (1993) 12, 621-630, International Patent
Publication WO 95-09873, French Patent Application FR 2694767, U.S.
Pat. No. 521,628). A humanized PM-1 antibody has been known that
was obtained by transplanting the complementarity determining
region (CDR) of one of them, a mouse antibody PM-1 (Hirata, Y. et
al., J. Immunology (1989) 143, 2900-2906), to a human antibody (the
International Patent Publication WO 92-19759).
[0051] The above IL-6 antagonist is preferably an antibody against
IL-6 receptor, preferably a monoclonal antibody against human IL-6
receptor or a monoclonal antibody against mouse IL-6 receptor. As
the above monoclonal antibody against human IL-6 receptor, there
can be illustrated PM-1 antibody, and as the above monoclonal
antibody against mouse IL-6 receptor, there can be illustrated
MR16-1 antibody. The above antibody is preferably a chimeric
antibody, humanized antibody or a human antibody, for example a
humanized PM-1 antibody.
[0052] IL-6 antagonists for use in the present invention may be of
any origin, any kind, and any form, as long as they are useful as
an active ingredient for a preventive or therapeutic effect for
vasculitis.
[0053] IL-6 antagonists block signal transduction by IL-6 and
inhibit the biological activity of IL-6. IL-6 antagonists are
preferably substances that have an activity of inhibiting any of
IL-6, IL-6 receptor, and gp130. As the IL-6 antagonists, there can
be mentioned, for example, anti-IL-6 antibody, anti-IL-6 receptor
antibody, anti-gp130 antibody, altered IL-6, altered soluble IL-6
receptor, a partial peptide of IL-6 or IL-6 receptor, and a low
molecular weight substances having the same activity as these.
[0054] Anti-IL-6 antibodies for use in the present invention can be
obtained as polyclonal or monoclonal antibodies using a known
method. As the anti-IL-6 antibodies for use in the present
invention, monoclonal antibodies of, in particular, a mammalian
origin, are preferred. Monoclonal antibodies of a mammalian origin
include those produced by a hybridoma and recombinant antibody
produced by a host which has been transformed with an expression
vector containing genetically engineered antibody genes. These
antibodies, via binding to IL-6, block the binding of IL-6 to IL-6
receptor, and thereby blocks signal transduction of the biological
activity of IL-6 into the cell.
[0055] Examples of such antibodies include MH166 (Matsuda et al.,
Eur. J. Immunol. (1988) 18, 951-956) and SK2 antibody (Sato, K. et
al., The 21st Nihon Menekigakkai Soukai (General Meeting of the
Japan Immunology Society), Academic Record (1991) 21, 166) and the
like.
[0056] An anti-IL-6 antibody-producing hybridoma can be basically
constructed using a known procedure as described below. Thus, IL-6
may be used as a sensitizing antigen and is immunized in the
conventional method of immunization. The immune cells thus obtained
are fused with known parent cells in the conventional cell fusion
process, and then monoclonal antibody-producing cells are screened
by the conventional screening method to prepare the desired
hybridoma.
[0057] Specifically, anti-IL-6 antibody may be obtained in the
following manner. For example, a human IL-6 for use as the
sensitizing antigen to obtain antibody can be obtained using the
IL-6 gene/amino acid sequence disclosed in Eur. J. Biochem (1987)
168, 543-550, J. Immunol. (1988) 140, 1534-1541, or Argic. Biol.
(1990) 54, 2685-2688.
[0058] After a suitable host cell is transformed by inserting the
IL-6 gene sequence into a known expression vector system, the IL-6
protein of interest is purified from the host cell or the culture
supernatant thereof, and the purified IL-6 protein can be used as
the sensitizing antigen. Alternatively, a fusion protein of the
IL-6 protein and another protein may be used as the sensitizing
antigen.
[0059] Anti-IL-6 receptor antibodies for use in the present
invention can be obtained as polyclonal or monoclonal antibodies
using a known method. As the anti-IL-6 antibodies for use in the
present invention, monoclonal antibodies of, in particular, a
mammalian origin, are preferred. Monoclonal antibodies of a
mammalian origin include those produced by a hybridoma and those
produced by a host which has been transformed with an expression
vector containing genetically engineered antibody genes. The
antibodies, via binding to IL-6 receptor, inhibit the binding of
IL-6 to IL-6 receptor, and thereby block the transduction of the
biological activity of IL-6 into the cell.
[0060] Examples of such antibodies include MR16-1 antibody (Tamura,
T., et al., Proc. Natl. Acad. Sci. USA (1993) 90, 11924-11928),
PM-1 antibody (Hirata, et al., J. Immunol. (1989) 143, 2900-2906),
or AUK12-20 antibody, AUK64-7 antibody or AUK146-15 antibody
(International Patent Publication WO 92-19759), and the like. Among
them, PM-1 antibody is most preferred.
[0061] Incidentally, the hybridoma cell line which produces PM-1
antibody has been internationally deposited under the provisions of
the Budapest Treaty as PM-1 on Jul. 12, 1995 with the Patent
Microorganism Depository of the National Institute of Industrial
Science and Technology, at Chuo 6, 1-1, Higashi 1-chome, Tsukuba
city, Ibaraki pref., Japan, as FERM BP-2998. The hybridoma cell
line which produces MR16-1 antibody has been internationally
deposited under the provisions of the Budapest Treaty as MR16-1 on
Mar. 13, 1997 with the Patent Microorganism Depository of the
National Institute of Industrial Science and Technology, at Chuo 6,
1-1, Higashi 1-chome, Tsukuba city, Ibaraki pref., Japan, as FERM
BP-5875.
[0062] Hybridomas producing anti-IL-6 receptor monoclonal antibody
can be basically prepared using a known procedure as described
below. Thus, IL-6 receptor is used as a sensitizing antigen and is
immunized according to the conventional method of immunization. The
immune cells thus obtained are fused with known parent cells in the
conventional cell fusion process, and then monoclonal
antibody-producing cells may be screened by the conventional
screening method to prepare the desired hybridoma.
[0063] Specifically, anti-IL-6 receptor antibody may be prepared in
the following manner. For example, the human IL-6 receptor used as
the sensitizing antigen for obtaining antibody can be obtained
using the IL-6 receptor gene sequence/amino acid sequence disclosed
in European Patent Application EP 325474, and the mouse IL-6
receptor can be obtained using the IL-6 receptor gene disclosed in
Japanese Unexamined Patent Publication (Kokai) 3-155795.
[0064] There are two types of IL-6 receptor proteins: IL-6 receptor
expressed on the cell membrane, and IL-6 receptor detached from the
cell membrane (soluble IL-6 Receptor) (Yasukawa et al., J. Biochem.
(1990) 108, 673-676). Soluble IL-6 receptor antibody is composed
substantially of the extracellular region of the IL-6 receptor
bound to the cell membrane and, thereby, is different from the
membrane-bound IL-6 receptor in that the former lacks the
transmembrane region or both of the transmembrane region and the
intracellular region. As the IL-6 receptor protein, any IL-6
receptor can be used, as long as it can be used a sensitizing
antigen for production of the IL-6 receptor antibody for use in the
present invention.
[0065] After the gene sequence of IL-6 receptor is inserted into a
known expression vector system to transform an appropriate host
cell, the desired IL-6 receptor protein may be purified from the
host cell or a culture supernatant thereof using a known method,
and the purified IL-6 receptor protein thus purified may be used as
the sensitizing antigen. Alternatively, cells that are expressing
IL-6 receptor or a fusion protein of the IL-6 receptor protein and
another protein may be used as the sensitizing antigen.
[0066] E. coli that has a plasmid pIBIBSF2R containing cDNA
encoding human IL-6 receptor has been internationally deposited
under the provisions of the Budapest Treaty as HB101-pIBIBSF2R on
Jan. 9, 1989 with the Patent Microorganism Depository of the
National Institute of Industrial Science and Technology, at Chuo 6,
1-1, Higashi 1-chome, Tsukuba city, Ibaraki pref., Japan, as FERM
BP-2232.
[0067] Anti-gp130 antibodies for use in the present invention can
be obtained as polyclonal or monoclonal antibodies using a known
method. As the anti-gp130 antibodies for use in the present
invention, monoclonal antibodies of, in particular, a mammalian
origin, are preferred. Monoclonal antibodies of a mammalian origin
include those produced by a hybridoma and those produced by a host
which has been transformed with an expression vector containing
genetically engineered antibody genes. The antibodies, via binding
to gp130, inhibit the binding of IL-6/IL-6 receptor complex to
gp130, and thereby block the transduction of the biological
activity of IL-6 into the cell.
[0068] Examples of such antibodies include AM64 antibody (Japanese
Unexamined Patent Publication (Kokai) 3-219894), 4B11 antibody and
2H4 antibody (U.S. Pat. No. 5,571,513), B-S12 antibody and B-P8
antibody (Japanese Unexamined Patent Publication (Kokai)
8-291199).
[0069] An anti-gp130 monoclonal antibody-producing hybridoma can be
basically created using a known procedure as described below. Thus,
gp130 may be used as a sensitizing antigen and is immunized in the
conventional method of immunization. The immune cells thus obtained
are fused with known parent cells in the conventional cell fusion
process and, then, the monoclonal antibody-producing hybridomas are
screened by the conventional screening method to prepare the
desired hybridoma.
[0070] Specifically, monoclonal antibody may be obtained in the
following manner. For example, gp130 used as the sensitizing
antigen for antibody generation can be obtained using the gp130
gene sequence/amino acid sequence disclosed in European Patent
Application EP 411946.
[0071] After a suitable host cell is transformed by inserting the
gp130 gene sequence into a known expression vector system, the
gp130 protein of interest is purified from the host cell or from
the culture supernatant thereof. The purified gp130 receptor
protein can be used as the sensitizing antigen. Alternatively, a
fusion protein of the gp130 protein and another protein may be used
as the sensitizing antigen.
[0072] Though mammals to be immunized with the sensitizing antigen
are not specifically limited, they are preferably selected in
consideration of their compatibility with the parent cell for use
in cell fusion. They generally include rodents such as mice, rats,
hamsters and the like.
[0073] Immunization of animals with a sensitizing antigen is
carried out using a known method. A general method, for example,
involves the intraperitoneal or subcutaneous administration of a
sensitizing antigen to the mammal. Specifically, a sensitizing
antigen which has been diluted and suspended in an appropriate
amount of phosphate buffered saline (PBS) or physiological saline
etc. is mixed, as desired, with an appropriate amount of a common
adjuvant, for example Freund's complete adjuvant. After being
emulsified, it is preferably administered to a mammal for several
times every 4 to 21 days. Alternatively a suitable carrier may be
used at the time of immunization of the sensitizing antigen.
[0074] After immunization and the confirmation of the increase in
the desired antibody levels in the serum, the immune cells are
taken out from the mammal and are subjected to cell fusion.
Preferred immune cells to be subjected to cell fusion include, in
particular, the spleen cells.
[0075] The mammalian myeloma cells as the other parent cells which
are fused with the above-mentioned immune cells preferably include
various known cell lines such as P3X63Ag8.653 (Kearney, J. F. et
al., C. Immunol. (1979) 123; 1548-1550), P3X63Ag8U.1 (Current
Topics in Microbiology and Immunology (1978) 81; 1-7), NS-1
(Kohler, G. and Milstein, C., Eur. J. Immunol. (1976) 6; 511-519),
MPC-11 (Margulies, D. H. et al., Cell (1976) 8; 405-415), SP2/0
(Shulman, M. et al., Nature (1978) 276; 269-270), FO (de St. Groth,
S. F. et al., J. Immunol. Methods (1980) 35; 1-21), S194
(Trowbridge, I. S., J. Exp. Med. (1978) 148; 313-323), R210
(Galfre, G. et al., Nature (1979) 277; 131-133) and the like.
[0076] Cell fusion between the above immune cells and the myeloma
cells may be essentially conducted in accordance with a known
method such as is described in Milstein et al. (Kohler, G. and
Milstein, C., Methods Enzymol. (1981) 73; 3-46) and the like.
[0077] More specifically, the above cell fusion is carried out in a
conventional nutrient broth in the presence of, for example, a cell
fusion accelerator. As the cell fusion accelerator, for example,
polyethylene glycol (PEG), Sendai virus (HVJ) and the like may be
used, and, in addition, an adjuvant such as dimethyl sulfoxide etc.
may be added as desired to enhance the efficiency of fusion.
[0078] The preferred ratio of the immune cells and the myeloma
cells to be used is, for example, 1 to 10 times more immune cells
than the myeloma cells. Examples of culture media to be used for
the above cell fusion include RPMI1640 medium and MEM culture
medium suitable for the growth of the above myeloma cell lines, and
the conventional culture medium used for this type of cell culture,
and besides a serum supplement such as fetal calf serum (FCS) may
be added.
[0079] In cell fusion, predetermined amounts of the above immune
cells and the myeloma cells are mixed well in the above culture
liquid, to which a PEG solution previously heated to about
37.degree. C., for example a PEG solution with a mean molecular
weight of about 1000 to 6000, is added at a concentration of 30 to
60% (w/v) and mixed to obtain the desired fusion cells (hybridoma).
Then by repeating the sequential addition of a suitable culture
liquid and centrifugation to remove the supernatant, cell fusion
agents etc. which are undesirable for the growth of the hybridoma
can be removed.
[0080] Said hybridoma is selected by culturing in the conventional
selection medium, for example, the HAT culture medium (a culture
liquid containing hypoxanthine, aminopterin, and thymidine).
Culturing in said HAT culture medium is continued generally for a
period of time sufficient to effect killing of the cells other than
the desired hybridoma (non-fusion cells), generally several days to
several weeks. The conventional limiting dilution method is
conducted in which the hybridomas that produce the desired antibody
are screened and monclonally cloned.
[0081] In addition to obtaining the above hybridoma by immunizing
an animal other than a human with an antigen, it is also possible
to sensitize human lymphocytes in vitro with a desired antigen or
desired antigen-expressing cells, and the resulting sensitized B
lymphocytes are fused with human myeloma cells, for example U266,
to obtain the desired human antibody having the activity of binding
to the desired antigen or the desired antigen-expressing cells (see
Japanese Post-examined Patent Publication (Kokoku) No. 1-59878).
Furthermore, a transgenic animal having a repertoire of all human
antibody genes can be immunized with the antigen or the
antigen-expressing cells to obtain the desired human antibody in
the method described above (see International Patent Publication WO
93/12227, WO 92/03918, WO 94/02602, WO 94/25585, WO 96/34096 and WO
96/33735).
[0082] The monoclonal antibody-producing hybridoma thus constructed
can be subcultured in the conventional culture liquid, or can be
stored for a prolonged period of time in liquid nitrogen.
[0083] In order to obtain monoclonal antibodies from said
hybridoma, a method can be used in which said hybridoma is cultured
in the conventional method and the antibodies are obtained as the
supernatant, or a method in which the hybridoma is administered to,
and grown in, a mammal compatible with said hybridoma and the
antibodies are obtained as the ascites. The former method is
suitable for obtaining high-purity antibodies, whereas the latter
is suitable for a large scale production of antibodies.
[0084] For example, a hybridoma producing anti-IL-6 receptor
antibody can be constructed using the method disclosed in Japanese
Unexamined Patent Publication (Kokai) 3-139293. It can be conducted
by a method in which the PM-1 antibody-producing hybridoma that was
internationally deposited under the provisions of the Budapest
Treaty as FERM BP-2998 on Jul. 12, 1989 with the Patent
Microorganism Depository of the National Institute of Industrial
Science and Technology, at Chuo 6, 1-1, Higashi 1-chome, Tsukuba
city, Ibaraki pref., Japan, is intraperitoneally injected to BALB/c
mice to obtain the ascites from which the PM-1 antibody is
purified, or a method in which said hybridoma is cultured in a
suitable culture medium such as the RPMI1640 medium containing 10%
bovine fetal serum and 5% MB-Condimed H1 (manufactured by
Boehringer Mannheim), the hybridoma SFM medium (manufactured by
GIBCO-BRL), the PFHM-II medium (manufactured by GIBCO-BRL) and the
like, and the PM-1 antibody can be purified from the
supernatant.
[0085] A recombinant antibody which was produced by the recombinant
gene technology in which an antibody gene was cloned from the
hybridoma and integrated into a suitable vector which was then
introduced into a host can be used in the present invention as
monoclonal antibody (see, for example, Borrebaeck C. A. K., and
Larrick J. W. THERAPEUTIC MONOCLONAL ANTIBODIES, published in the
United Kingdom by MACMILLAN PUBLISHERS LTD. 1990).
[0086] Specifically, mRNA encoding the variable (V) region of the
desired antibody is isolated from antibody-producing cells such as
a hybridoma. The isolation of mRNA is conducted by preparing total
RNA using, for example, a known method such as the guanidine
ultracentrifuge method (Chirgwin, J. M. et al., Biochemistry (1979)
18, 5294-5299), the AGPC method (Chomczynski, P. et al., Anal.
Biochem. (1987) 162, 156-159), and then mRNA is purified from the
total RNA using the mRNA Purification kit (manufactured by
Pharmacia) and the like. Alternatively, mRNA can be directly
prepared using the Quick Prep mRNA Purification Kit (manufactured
by Pharmacia).
[0087] cDNA of the V region of antibody may be synthesized from the
mRNA thus obtained using a reverse transcriptase. cDNA may be
synthesized using the AMV Reverse Transcriptase First-strand cDNA
Synthesis Kit and the like. Alternatively, for the synthesis and
amplification of cDNA, the 5'-Ampli FINDER RACE Kit (manufactured
by Clontech) and the 5'-RACE method (Frohman, M. A. et al., Proc.
Natl. Acad. Sci. USA (1988) 85, 8998-9002; Belyavsky, A. et al.,
Nucleic Acids Res. (1989) 17, 2919-2932) that employs polymerase
chain reaction (PCR) may be used. The desired DNA fragment is
purified from the PCR product obtained and may be ligated to vector
DNA. Moreover, a recombinant vector is constructed therefrom and
then is introduced into E. coli etc., from which colonies are
selected to prepare the desired recombinant vector. The base
sequence of the desired DNA may be confirmed by a known method such
as the dideoxy method.
[0088] Once the DNA encoding the V region of the desired antibody
has been obtained, it may be ligated to DNA encoding the constant
region (C region) of the desired antibody, which is then integrated
into an expression vector. Alternatively, the DNA encoding the V
region of the antibody may be integrated into an expression vector
containing DNA encoding the C region of the antibody. In order to
produce the antibody for use in the present invention, the antibody
gene is integrated as described below into an expression vector so
as to be expressed under the control of the expression regulatory
region, for example an enhancer and/or a promoter. Subsequently,
the expression vector may be transformed into a host cell and the
antibody can then be expressed therein.
[0089] In accordance with the present invention, an artificially
altered recombinant antibody such as chimeric antibody, humanized
antibody, and human antibody can be used for the purpose of
lowering heterologous antigenicity against humans. These altered
antibodies can be produced using known methods.
[0090] Chimeric antibody can be obtained by ligating the thus
obtained DNA encoding the V region of antibody to DNA encoding the
C region of human antibody, which is then integrated into an
expression vector and introduced into a host for production of the
antibody therein (see European Patent Application EP 125023, and
International Patent Publication WO 92-19759). Using this known
method, chimeric antibody useful for the present invention can be
obtained.
[0091] For example, a plasmid that contains DNA encoding the L
chain V region or the H chain V region of chimeric PM-1 antibody
was designated as pPM-k3 or pPM-h1, respectively, and E. coli
having the plasmid has been internationally deposited under the
provisions of the Budapest Treaty as NCIMB 40366 and NCIMB 40362,
respectively, on Feb. 12, 1991 with the National Collections of
Industrial and Marine Bacteria Limited (23 St Machar Drive,
Aberdeen, Scotland, AB2 1RY, United Kingdom of Great Britain and
Northern Ireland).
[0092] Humanized antibody, which is also called reshaped human
antibody, has been made by transplanting the complementarity
determining region (CDR) of antibody of a mammal other than a
human, for example mouse antibody, into the CDR of human antibody.
The general recombinant DNA technology for preparation of such
antibodies is also known (see European Patent Application EP 125023
and International Patent Publication WO 92-19759).
[0093] Specifically, a DNA sequence which was designed to ligate
the CDR of mouse antibody with the framework region (FR) of human
antibody is synthesized from several divided oligonucleotides
having sections overlapping with one another at the ends thereof.
The DNA thus obtained is ligated to the DNA encoding the C region
of human antibody and then is integrated into an expression vector,
which is introduced into a host for antibody production (see
European Patent Application EP 239400 and International Patent
Publication WO 92-19759).
[0094] For the FR of human antibody ligated through CDR, the
complementarity determining region that forms a favorable antigen
binding site is selected. When desired, amino acids in the
framework region of the antibody variable region may be substituted
so that the complementarity determining region of reshaped human
antibody may form an appropriate antigen biding site (Sato, K. et
al., Cancer Res. (1993) 53, 851-856).
[0095] For example, for chimeric antibody or humanized antibody,
the C region of human antibody is used. As the C region of human
antibody, there can be mentioned C.gamma., and C.gamma.1,
C.gamma.2, C.gamma.3, and C.gamma.4, for example, can be used. The
C region of human antibody may be modified to improve the stability
of antibody or the production thereof.
[0096] Chimeric antibody consists of the variable region of
antibody derived from a mammal other than the human and the C
region derived from human antibody, whereas humanized antibody
consists of the complementarity determining region of antibody
derived from a mammal other than the human and the framework region
and the C region of antibody derived from human antibody.
Accordingly, antigenicity thereof in the human body has been
reduced so that they are useful as an antibody for use in the
present invention.
[0097] As a preferred embodiment of the humanized antibody for use
in the present invention, there can be mentioned humanized PM-1
antibody (see International Patent Publication WO 92-19759).
[0098] Furthermore, as a method of obtaining human antibody, a
technology that employs panning with a human antibody library is
known, in addition to those described above. For example, the
variable region of human antibody is expressed on the surface of a
phage by the phage display method as a single chain antibody (scFv)
to select a phage that binds to the antigen. By analyzing the gene
of the phage selected, the DNA sequence encoding the variable
region of the human antibody that binds to the antigen can be
determined. Once the DNA sequence of scFv that binds to the antigen
is clarified, it is possible to construct an appropriate expression
vector that contains said sequence and then to obtain a human
antibody. These methods are already known and can be found in WO
92/01047, WO 92/20791, WO 93/06213, WO 93/11236, WO 93/19172, WO
95/01438, and WO 95/15388.
[0099] Antibody genes constructed as described above may be
expressed and obtained in a known method. In the case of mammalian
cells, expression may be accomplished using a vector containing a
commonly used useful promoter, the antibody gene to be expressed,
DNA in which the poly A signal has been operably linked at 3'
downstream thereof or a vector containing said DNA. Examples of the
promoter/enhancer include human cytomegalovirus immediate early
promoter/enhancer.
[0100] Additionally, as the promoter/enhancer which can be used for
expression of antibody for use in the present invention, there can
be used viral promoters/enhancers such as retrovirus, polyoma
virus, adenovirus, and simian virus 40 (SV40), and
promoters/enhancers derived from mammalian cells such as human
elongation factor 1.alpha.(HEF1.alpha.).
[0101] For example, expression may be readily accomplished by the
method of Mulligan et al. (Mulligan, R. C. et al., Nature (1979)
277, 108-114) when SV40 promoter/enhancer is used, or by the method
of Mizushima et al. (Mizushima, S. and Nagata, S. Nucleic Acids
Res. (1990) 18, 5322) when HEF1.alpha. promoter/enhancer is
used.
[0102] In the case of E. coli, expression may be conducted by
operably linking a commonly used useful promoter, a signal sequence
for antibody secretion, and the antibody gene to be expressed,
followed by expression thereof. As the promoter, for example, there
can be mentioned lacZ promoter and araB promoter. The method of
Ward et al. (Ward, E. S. et al., Nature (1098) 341, 544-546; Ward,
E. S. et al., FASEB J. (1992) 6, 2422-2427) may be used when lacz
promoter is used, and the method of Better et al. (Better, M. et
al., Science (1988) 240, 1041-1043) may be used when araB promoter
is used.
[0103] As the signal sequence for antibody secretion when produced
in the periplasm of E. coli, the pelB signal sequence (Lei, S. P.
et al., J. Bacteriol. (1987) 169, 4379-4383) can be used. After
separating the antibody produced in the periplasm, the structure of
the antibody is appropriately refolded before use (see, for
example, WO 96/30394).
[0104] As the origin of replication, there can be used those
derived from SV40, polyoma virus, adenovirus, bovine papilloma
virus (BPV) and the like. Furthermore, for the amplification of the
gene copy number in the host cell system, expression vectors can
include as selectable markers the aminoglycoside phosphotransferase
(APH) gene, the thymidine kinase (TK) gene, E. coli xanthine
guanine phosphoribosyl transferase (Ecogpt) gene, the dihydrofolate
reductase (dhfr) gene and the like.
[0105] For the production of antibody for use in the present
invention, any production system can be used, The production system
for antibody preparation comprises the in vitro or the in vivo
production system. As the in vitro production system, there can be
mentioned a production system which employs eukaryotic cells and
the production system which employs prokaryotic cells.
[0106] When the eukaryotic cells are used, there are the production
systems which employ animal cells, plant cells, or fungal cells.
Known animal cells include (1) mammalian cells such as CHO cells,
COS cells, myeloma cells, baby hamster kidney (BHK) cells, HeLa
cells, and Vero cells, (2) amphibian cells such as Xenopus oocytes,
or (3) insect cells such as sf9, sf21, and Tn5. Known plant cells
include, for example, those derived from Nicotiana tabacum, which
may be subjected to callus culture. Known fungal cells include
yeasts such as the genus Saccharomyces, more specifically
Saccharomyces cereviceae, or filamentous fungi such as the genus
Aspergillus, more specifically Aspergillus niger.
[0107] When the prokaryotic cells are used, there are the
production systems which employ bacterial cells, Known bacterial
cells include Escherichia coli (E. coli), and Bacillus
subtilis.
[0108] By introducing, via transformation, the gene of the desired
antibody into these cells and culturing the transformed cells in
vitro, the antibody can be obtained. Culturing is conducted in the
known methods. For example, as the culture liquid, DMEM, MEM,
RPMI1640, and IMDM can be used, and serum supplements such as fetal
calf serum (FCS) may be used in combination. In addition,
antibodies may be produced in vivo by implanting cells into which
the antibody gene has been introduced into the abdominal cavity of
an animal and the like.
[0109] As in vivo production systems, there can be mentioned those
which employ animals and those which employ plants. When animals
are used, there are the production systems which employ mammals and
insects.
[0110] As mammals, goats, pigs, sheep, mice, and cattle can be used
(Vicki Glaser, SPECTRUM Biotechnology Applications, 1993). Also, as
insects, silkworms can be used. When plants are used, tobacco, for
example, can be used.
[0111] Antibody genes are introduced into these animals or plants,
and the antibodies are produced in such animals or plants, and
recovered. For example, an antibody gene is inserted into the
middle of the gene encoding protein which is inherently produced in
the milk such as goat .beta. casein to prepare fusion genes. DNA
fragments containing the fusion gene into which the antibody gene
has been inserted are injected into a goat embryo, and the embryo
is introduced into a female goat. The desired antibody is obtained
from the milk produced by the transgenic goat born to the goat who
received the embryo or offsprings thereof. In order to increase the
amount of milk containing the desired antibody produced by the
transgenic goat, hormones may be given to the transgenic goat as
appropriate. (Ebert, K. M. et al., Bio/Technology (1994) 12,
699-702).
[0112] When silkworms are used, baculovirus into which the desired
antibody gene has been inserted is infected to the silkworm, and
the desired antibody can be obtained from the body fluid of the
silkworm (Maeda, S. et al., Nature (1985) 315, 592-594). Moreover,
when tobacco is used, the desired antibody gene is inserted into an
expression vector for plants, for example pMON 530, and then the
vector is introduced into a bacterium such as Agrobacterium
tumefaciens. The bacterium is then infected to tobacco such as
Nicotiana tabacum to obtain the desired antibody from the leaves of
the tobacco (Julian, K.-C. Ma et al., Eur. J. Immunol. (1994) 24,
131-138).
[0113] When antibody is produced in in vitro or in in vivo
production systems, as described above, DNA encoding the heavy
chain (H chain) or the light chain (L chain) of antibody may be
separately integrated into an expression vector and the hosts are
transformed simultaneously, or DNA encoding the H chain and the L
chain may be integrated into a single expression vector, and the
host is transformed therewith (see International Patent Publication
WO 94-11523).
[0114] Antibodies for use in the present invention may be antibody
fragments or modified versions thereof as long as they are
preferably used. For example, as fragments of antibody, there may
be mentioned Fab, F(ab').sub.2, Fv or single-chain Fv (scFv) in
which Fv's of H chain and L chain were ligated via a suitable
linker.
[0115] Specifically, antibodies are treated with an enzyme, for
example, papain or pepsin, to produce antibody fragments, or genes
encoding these antibody fragments are constructed, and then
introduced into an expression vector, which is expressed in a
suitable host cell (see, for example, Co, M. S. et al., J. Immunol.
(1994) 152, 2968-2976; Better, M. and Horwitz, A. H., Methods in
Enzymology (1989) 178, 476-496; Plueckthun, A. and Skerra, A.,
Methods in Enzymology (1989) 178, 476-496; Lamoyi, E., Methods in
Enzymology (1989) 121, 652-663; Rousseaux, J. et al., Methods in
Enzymology (1989) 121, 663-66; Bird, R. E. et al., TIBTECH (1991)
9, 132-137).
[0116] scFv can be obtained by ligating the V region of H chain and
the V region of L chain of antibody. In scFv, the V region of H
chain and the V region of L chain are preferably ligated via a
linker, preferably a peptide linker (Huston, J. S. et al., Proc.
Natl. Acad. Sci. USA (1988) 85, 5879-5883). The V region of H chain
and the V region of L chain in scFv may be derived from any of the
above-mentioned antibodies. As the peptide linker for ligating the
V regions, any single-chain peptide comprising, for example, 12-19
amino acid residues may be used.
[0117] DNA encoding scFv can be obtained using DNA encoding the H
chain or the H chain V region of the above antibody and DNA
encoding the L chain or the L chain V region of the above antibody
as the template by amplifying the portion of the DNA encoding the
desired amino acid sequence among the above sequences by the PCR
technique with the primer pair specifying the both ends thereof and
by further amplifying the combination of DNA encoding the peptide
linker portion and the primer pair which defines that both ends of
said DNA be ligated to the H chain and the L chain,
respectively.
[0118] Once DNAs encoding scFv have been constructed, an expression
vector containing them and a host transformed with said expression
vector can be obtained by the conventional methods, and scFv can be
obtained using the resultant host by the conventional methods.
[0119] These antibody fragments can be produced by obtaining the
gene thereof in a similar manner to that mentioned above and by
allowing it to be expressed in a host. "Antibody" as used herein
also encompasses these antibody fragments.
[0120] As modified antibodies, antibodies associated with various
molecules such as polyethylene glycol (PEG) can be used. "Antibody"
as used herein also encompasses these modified antibodies. These
modified antibodies can be obtained by chemically modifying the
antibodies thus obtained. These methods have already been
established in the art.
[0121] Antibodies produced and expressed as described above can be
separated from the inside or outside of the host cell and then may
be purified to homogeneity. Separation and purification of the
antibody for use in the present invention may be accomplished by
affinity chromatography. As the column used for such affinity
chromatography, there can be mentioned Protein A column and Protein
G column. Examples of the carriers used in the Protein A column are
Hyper D, POROS, Sepharose F. F. and the like. Alternatively,
methods for separation and purification conventionally used for
proteins can be used without any limitation.
[0122] Separation and purification of the antibody for use in the
present invention may be accomplished by combining, as appropriate,
chromatography other than the above-mentioned affinity
chromatography, filtration, ultrafiltration, salting-out, dialysis
and the like. Chromatography includes, for example, ion exchange
chromatography, hydrophobic chromatography, gel-filtration and the
like. These chromatographies can be applied into high performance
liquid chromatography (HPLC). Alternatively, reverse-phase HPLC can
be used.
[0123] The concentration of antibody obtained in the above can be
determined by the measurement of absorbance or by the enzyme-linked
immunosorbent assay (ELISA) and the like. Thus, when absorbance
measurement is employed, a sample is appropriately diluted with
PBS(-) and then the absorbance is measured at 280 nm, followed by
calculation using the absorption coefficient of 1.35 OD at 1 mg/ml.
When the ELISA method is used, measurement is conducted as follows.
Thus, 100 .mu.l of goat anti-human IgG (manufactured by TAG)
diluted to 1 .mu.g/ml in 0.1 M bicarbonate buffer, pH 9.6, is added
to a 96-well plate (manufactured by Nunc), and is incubated
overnight at 4.degree. C. to immobilize the antibody. After
blocking, 100 .mu.l each of an appropriately diluted antibody of
the present invention or a sample containing the antibody, or 100
.mu.l of human IgG (manufactured by CAPPEL) as the standard is
added, and incubated at room temperature for 1 hour.
[0124] After washing, 100 .mu.l of 5000-fold diluted alkaline
phosphatase-labeled anti-human IgG antibody (manufactured by BIO
SOURCE) is added, and incubated at room temperature for 1 hour.
After washing, the substrate solution is added and incubated,
followed by the measurement of absorbance at 405 nm using the
MICROPLATE READER Model 3550 (manufactured by Bio-Rad) to calculate
the concentration of the desired antibody.
[0125] The altered IL-6 for use in the present invention has an
activity of binding to IL-6 receptor and does not transmit the
biological activity of IL-6. Thus, the altered IL-6, though it
competes with IL-6 for binding to IL-6 receptor, does not transmit
the biological activity of IL-6, and thereby it blocks signal
transduction by IL-6.
[0126] Altered IL-6 may be constructed through the introduction of
mutation by replacing amino acid residues of the amino acid
sequence of IL-6. IL-6, the source of the altered IL-6, may be of
any origin, but when the antigenicity is to be considered, it is
preferably human IL-6.
[0127] Specifically, the secondary structure of IL-6 is predicted
using a known molecular modeling program of the amino acid
sequencer for example WHATIF (Vriend et al., J. Mol. Graphics
(1990), 8, 52-56), and the overall effects on the amino acid
residue to be replaced is evaluated. After an appropriate amino
acid residue has been determined, mutation is introduced to effect
amino acid substitution by the commonly used polymerase chain
reaction (PCR) method using a vector containing the base sequence
encoding human IL-6 gene as a template thereby to obtain a gene
encoding an altered IL-6. This is then integrated, as desired, into
an appropriate expression vector, from which the altered IL-6 can
be obtained according to the expression, production and
purification methods of said recombinant antibody.
[0128] Specific examples of the altered IL-6 are disclosed in
Brakenhoff et al., J. Biol. Chem. (1994) 269, 86-93, and Savino et
al., EMBO J. (1994) 13, 1357-1367, WO 96-18648, and WO
96-17869.
[0129] The IL-6 partial peptide or the IL-6 receptor partial
peptide for use in the present invention has an activity of binding
to IL-6 receptor or IL-6, respectively, and does not transmit the
biological activity of IL-6. Thus, the IL-6 partial peptide or the
IL-6 receptor partial peptide specifically inhibits the binding of
IL-6 to IL-6 receptor by binding to IL-6 receptor or IL-6,
respectively, and thereby capturing it. As a result, they do not
transmit the biological activity of IL-6, and thus block signal
transduction of IL-6.
[0130] The IL-6 partial peptide or the IL-6 receptor partial
peptide is a peptide comprising some or all of the amino acid
sequence of the region involved in the binding to IL-6 and IL-6
receptor in the amino acid sequence of IL-6 or IL-6 receptor. Such
a peptide generally comprises 10-80, preferably 20-50, more
preferably 20-40 amino acid residues.
[0131] The IL-6 partial peptide or the IL-6 receptor partial
peptide can be constructed by specifying the region involved in the
binding to IL-6 and IL-6 receptor in the amino acid sequence of
IL-6 or IL-6 receptor, and by producing some or all of the amino
acid sequence by a conventional method such as a genetic
engineering technology or a peptide synthesis method.
[0132] In order to prepare the IL-6 partial peptide or the IL-6
receptor partial peptide by a genetic engineering technology, the
DNA sequence encoding the desired peptide is integrated into an
expression vector, from which the peptide can be obtained by the
expression, production, and purification methods of said
recombinant antibody. Preparation of the IL-6 partial peptide or
the IL-6 receptor partial peptide by the peptide synthesis method
can be effected using a method commonly used in peptide synthesis
such as the solid phase synthesis or the liquid phase
synthesis.
[0133] Specifically the method described in Zoku-Iyakuhin no
Kaihatsu (Sequel to Development of Pharmaceuticals), Vol. 14,
Peputido Gousei (Peptide Synthesis), edited by Haruaki Yajima,
Hirokawa Shoten, 1991, may be used. The solid phase synthesis
method used includes, for example, a reaction in which an amino
acid corresponding to the C-terminal of the peptide to be
synthesized is coupled to a support which is insoluble in organic
solvents, and then an amino acid in which .alpha.-amino group or a
side chain functional group has been protected with an appropriate
protecting group is condensed one amino acid at a time from the
C-terminal to the N-terminal direction, and a reaction in which
said protecting group of the .alpha.-amino group of the amino acid
or the peptide coupled to the resin is eliminated are alternately
repeated to elongate the peptide chain. The solid phase peptide
synthesis methods are divided into the Boc method and the Fmoc
method depending on the type of protecting group to be used.
[0134] After the synthesis of the desired peptide is complete, a
deprotection reaction and a reaction for cleaving the peptide chain
from the support is carried out. For cleavage from the peptide
chain, hydrogen fluoride or trifuluoromethane sulfonic acid in the
Boc method, and TFA in the Fmoc method are generally used. In the
Boc method, for example, the above peptide resin is treated in
hydrogen fluoride in the presence of anisole. Subsequently, the
protecting group is eliminated and the peptide is recovered by
cleaving from the support. By lyophilizing this, a crude peptide
can be obtained. On the other hand, in the Fmoc method, the
deprotection reaction and the cleavage reaction of the peptide from
the support may be performed in TFA for example, in a manner
procedure similar to the above.
[0135] The crude peptide thus obtained can be applied to HPLC for
its separation and purification. Its elution can be carried out in
a water-acetonitrile solvent system that is commonly used for
protein purification under an optimum condition. The fraction
corresponding to the peak of the profile of the chromatography
obtained is collected and lyophilized. The peptide fraction thus
purified is identified by subjecting it to the analysis of
molecular weight by mass spectroscopic analysis, the analysis of
amino acid composition, or the analysis of amino acid sequence, and
the like.
[0136] Specific examples of the IL-6 partial peptide or the IL-6
receptor partial peptide are disclosed in Japanese Unexamined
Patent Publication (Kokai) 2-188600, Japanese Unexamined Patent
Publication (Kokai) 7-324097, Japanese Unexamined Patent
Publication (Kokai) 8-311098, and United States Patent Publication
U.S. Pat. No. 5,210,075.
[0137] The activity of the IL-6 antagonist for use in the present
invention of blocking signal transduction of IL-6 can be evaluated
using a conventionally known method. Specifically, the
IL-6-dependent human myeloma cell line (S6B45, KPMM2), human
Lennert's T-lymphoma cell line KT3, or IL-6-dependent cell
MH60.BSF2 is cultured, to which IL-6 is added, and the activity can
be evaluated using the incorporation of .sup.3H-thymidine into the
IL-6-dependent cell in the coexistence of the IL-6 antagonist.
[0138] Alternatively, U266, a IL-6 receptor-expressing cell, may be
culture, to which .sup.125I-labeled IL-6 is added and an IL-6
antagonist is added at the same time, and then the
.sup.125I-labeled IL-6 bound to the IL-6 receptor-expressing cell
is determined. In the above assay system, a negative control group
containing no IL-6 antagonists, in addition to the group in which
an IL-6 receptor antagonist is present, is set up, and the results
obtained for them are compared to evaluate the IL-6-inhibiting
activity of the IL-6 receptor antagonist.
[0139] As described in the Example below, anti-IL-6 receptor
antibody exhibited a therapeutic effect of vasculitis, suggesting
that IL-6 antagonists such as anti-IL-6 receptor antibody are
effective as a therapeutic agent for vasculitis.
[0140] The subject to be treated in the present invention is
mammals. The subject mammal to be treated is preferably humans.
[0141] The preventive or therapeutic agents of the present
invention may be administered, either orally or parenterally,
systemically or locally. For example, intravenous injection such as
drip infusion, intramuscular injection, intraperitoneal injection,
subcutaneous injection, suppositories, intestinal lavage, oral
enteric coated tablets, and the like can be selected, and the
method of administration may be chosen, as appropriate, depending
on the age and the conditions of the patient. The effective dosage
is chosen from the range of 0.01 mg to 100 mg per kg of body weight
per administration. Alternatively, the dosage in the range of 1 to
20 mg, preferably 2 to 8 mg per patient may be chosen.
[0142] Preferred dosages and preferred methods of administration
are such that, in the case of anti-IL-6 receptor antibody, amounts
wherein free antibody is present in the blood are effective
dosages. In specific examples, 1 mg to 20 mg per kg of body weight,
preferably 2 mg to 8 mg, per month (4 weeks) are administered in
one to several doses, for example twice per week, once per week,
once every two weeks, once every four weeks, and the like by
intravenous injection such as drip infusion and subcutaneous
injection. The administration schedule can be adjusted by observing
the disease conditions and blood levels of laboratory tests by, for
example, extending the administration interval from twice per week
or once per week to once per two weeks, once per three weeks, once
per four weeks, and the like.
[0143] The preventive or therapeutic agents for vasculitis of the
present invention may contain pharmaceutically acceptable carriers
or additives depending on the route of administration. Examples of
such carriers or additives include water, a pharmaceutical
acceptable organic solvent, collagen, polyvinyl alcohol,
polyvinylpyrrolidone, a carboxyvinyl polymer,
carboxymethylcellulose sodium, polyacrylic sodium, sodium alginate,
water-soluble dextran, carboxymethyl starch sodium, pectin, methyl
cellulose, ethyl cellulose, xanthan gum, gum Arabic, casein,
gelatin, agar, diglycerin, propylene glycol, polyethylene glycol,
Vaseline, paraffin, stearyl alcohol, stearic acid, human serum
albumin (HSA), mannitol, sorbitol, lactose, a pharmaceutically
acceptable surfactant and the like. Additives used are chosen from,
but not limited to, the above or combinations thereof depending on
the dosage form.
EXAMPLES
[0144] The present invention will now be explained in more details
with reference to the working examples and reference examples. It
should be noted, however, that the present invention is not limited
by them in any way.
Working Example 1
Method:
[0145] Patients with intractable vasculitis syndrome (polyarteritis
nodosa, the aortitis syndrome) refractory to the conventional
therapy were subjected to treatment with humanized anti-IL-6
receptor antibody. Under the permission by the Advanced Medical
Treatment Committee of the Osaka University Hospital, two patients
received humanized PM-1 antibody (MRA) that is a humanized
anti-IL-6 receptor antibody. The end-point was the improvement in
evaluation of images by magnetic resonance imaging (MRI) and
computerized tomography (CT), improvement in skin conditions,
improvement in inflammatory markers such as C reactive protein
(CRP), and improvement in QOL (pain, arthralgia, malaise) Also,
peripheral blood cell counts, general biochemistry, homostatic
function, IL-6, soluble IL-6 receptor, the concentration of
humanized anti-IL-6 receptor antibody in the blood, tumor necrosis
factor .alpha. (TNF.alpha.), interleukin-1b (IL-1b), and vascular
epidermal growth factor (VEGF) were evaluated.
Result:
Case 1:
[0146] A 19-year old female. Diagnosed as having the aortitis
syndrome in 1996. Had a complication of ulcerative colitis.
Prednisolone (PSL) 60 mg/day was started. Even the combined use of
cyclosporin could not reduce PSL to 20 mg/day or lower. In 1998, in
response to aggravation, cyclophosphamide 150 mg/day was used in
addition to the methyl prednisolone (mPSL) pulse therapy, but could
not be reduced to 30 mg/day or lower. Betamethasone 1 mg/day was
added, and then leukopheresis was performed for seven times, but
without effect. In 2000 and after, the mPSL pulse therapy was
intermittently used, and azathioprine 100 mg/day, mycophenolate
mofetil 2 g/day, and methotrexate 17.5 mg/week were used in
combination, but without effect.
[0147] As shown in FIGS. 1-6, CT revealed the prominent hypertrophy
of the blood vessel wall in the ascending aorta, the aortic arch
trifurcation, and the descending aorta. Stenosis was noted in the
left subclavian artery (1t. SCA). Severe inflammation was noted
with CRP 12.6 mg/dl, and due to a severe persistent chest pain, a
reduction in body weight of 5 kg per month, and attacks of
unconsciousness occurred, the drip infusion of MRA 200 mg/week was
used. About two weeks later, CRP turned negative. One month later,
chest pain improved, and as seen in FIGS. 1-6, improvement in the
hypertrophy of the blood vessel wall in the ascending aorta, the
aortic arch trifurcation and the descending aorta, and enlargement
of the lumen of the blood vessels were observed and, furthermore,
the blood flow in carotid artery improved. Also fecal hemoglobin
turned negative, and symptoms of ulcerative colitis disappeared.
During the MRA therapy, blood levels of TNF.alpha. increased, but
without any aggravation in symptoms. Improvement in the hypertrophy
of the aorta wall and enlargement of the lumen of the blood vessels
were maintained even at the time of two years after the MRA
therapy. Takayasu's arteritis is also termed as the pulseless
disease, and in this patient as well the pulse could not be felt,
but after treatment the pulsation of arteries of the radius and the
cubitus could be felt at the wrist. Due to a prolonged use of MRA,
blood levels of IL-6 decreased from 1720 pg/ml to 100 pg/ml.
Case 2:
[0148] A 42-year old male. In 1986, arteritis nodosa (the skin
type) developed, and despite treatments with PSL, azathiopurine,
colchicine and anti-coagulants, remission and aggravation repeated.
In 1995 and after, cyclophosphamide was used in combination with
the mPSL pulse therapy, but without effect. From 1997, bolus
administration of azathiopurine, cyctophosphamide and
.gamma.-globulin was started, and from 2000, the cyclophosphamide
pulse therapy and leukopheresis were started, but without effect.
Skin grafting was performed on the skin ulcer due to vasculitis,
but without effect, and, due to aggravation, right fibula removal
and B-K amputation were performed. Necrotic vasculitis further
aggravated, and the ulcer in the lower limb was enlarging. After
starting treatment with a humanized anti-IL-G receptor antibody 200
mg/week, fever and skin erythema and muscle pains that were
previously observed improved. Though the removal of the right thigh
could not be avoided, leukocyte counts normalized with reduced IL-6
in the blood, and no aggravation in skin ulcer was noted
thereafter.
Discussion:
[0149] Since MRA was effective for patients with intractable
vasculitis that could not be controlled by the conventional
treatments, it was suggested that the IL-6 inhibition treatment
could provide a novel method of treatment for vasculitis. This
means that IL-6 is indispensable for the establishment of pathology
of vasculitis. Also, as the reduction of IL-6 per se was noted in
all cases, it demonstrated that the IL-6 inhibition treatment not
only has an anti-inflammatory effect but acts on the essential
nature of vasculitis,
Reference Example 1
Preparation of Human Soluble IL-6 receptor
[0150] Soluble IL-6 receptor was prepared by the PCR method using a
plasmid pBSEF2R.236 containing cDNA that encodes IL-6 receptor
obtained according to the method of Yamasaki et al., (Yamasaki, K.
et al., Science (1988) 241, 825-828). Plasmid pBSF2R.236 was
digested with a restriction enzyme Sph I to obtain the cDNA of IL-6
receptor, which was then inserted into mp18 (manufactured by
Amersham). Using a synthetic oligoprimer designed to introduce a
stop codon into the cDNA of IL-6 receptor, a mutation was
introduced into the cDNA of IL-6 receptor by the PCR method using
the in vitro Mutagenesis System (manufactured by Amersham). The
procedure resulted in the introduction of a stop codon to the amino
acid at position 345, and gave cDNA encoding soluble IL-6
receptor.
[0151] In order to express the cDNA of soluble IL-6 receptor in CHO
cells, it was ligated to plasmid pSV (manufactured by Pharmacia) to
obtain plasmid pSVL344. The cDNA of soluble IL-6 receptor that was
cleaved with Hind III-Sal I was inserted to plasmid pECEdhfr
containing the cDNA of dhfr to obtain plasmid pECEdhfr344 that can
be expressed in the CHO cells.
[0152] Ten .mu.g of plasmid pECEdhfr344 was transfected to a
dhfr-CHO cell line DXB-11 (Urlaub G. et al., Proc. Natl. Acad. Sci.
USA (1980) 77, 4216-4220) by the calcium phosphate precipitation
method (Chen C. et al., Mol. Cell. Biol. (1987) 7, 2745-2751). The
transfected CHO cells were cultured for 3 weeks in a
nucleoside-free .alpha. MEM selection medium containing 1 mM
glutamine, 10% dialyzed FCS, 100 U/ml penicillin, and 100 .mu.g/ml
streptomycin.
[0153] The selected CHO cells were screened by the limiting
dilution method to obtain a single CHO cell clone. The CHO cell
clone was amplified in 20 nM-200 nM methotrexate (MTX) to obtain a
CHO cell line 5E27 that produces human soluble IL-6 receptor. The
CHO cell line 5E27 was cultured in an Iscov-modified Dulbecco's
medium (IMDM, manufactured by Gibco) containing 5% FBS. The culture
supernatant was collected and the concentration of soluble IL-6
receptor in the culture supernatant was determined by ELISA. The
result confirmed that soluble IL-6 receptor is present in the
culture supernatant.
Reference Example 2
Preparation of Human IL-6 Antibody
[0154] Ten .mu.g of the recombinant IL-6 (Hirano et al., Immunol.
Lett., (1988) 17, 41) was immunized to BALB/c mice together with
Freund's complete adjuvant, and this was repeated every week until
anti-IL-6 antibody could be detected in the serum. Immune cells
were extracted from local lymph node and were then fused with a
myeloma cell line P3U1 using polyethylene glycol 1500. Hybridomas
were selected according to the method of Oi et al. (Selective
Methods in Cellular Immunology, W.H. Freeman and Co., San
Francisco, 351, 1980) that employs the HAT medium, and a hybridoma
that produces anti-human IL-6 antibody was established.
[0155] The hybridoma that produces anti-human IL-6 antibody was
subjected to the IL-6 binding assay as follows. Thus, a 96-well
microtiter plate made of flexible polyvinyl (manufactured by
Dynatech Laboratories, Inc., Alexandria, Va.) was coated with 100
.mu.l of goat anti-mouse Ig (10.mu./ml, manufactured by Cooper
Biomedical, Inc., Malvern, Pa.) overnight at 4.degree. C.
Subsequently, the plate was treated with 100 .mu.l of PBS
containing 1% bovine serum albumin (BSA) at room temperature for 2
hours.
[0156] After washing in PBS, 100 .mu.l of the hybridoma culture
supernatant was added to each well, and then incubated overnight at
4.degree. C. The plate was washed, .sup.125I-labeled recombinant
IL-6 was added to each well to a concentration of 2000 cpm/0.5
ng/well, and then radioactivity of each well after washing was
determined by a gamma counter (Beckman Gamma 9000, Beckman
Instruments, Fullerton, Calif.). Of 216 hybridoma clones, 32 were
positive in the IL-6 binding assay. From these clones, stable
MH166.BSF2 was finally obtained. Anti-IL-6 antibody MH166 produced
by said hybridoma has a subtype of IgG1 .kappa..
[0157] Then, the IL-6-dependent mouse hybridoma clone MH60.BSF2 was
used to examine a neutralizing activity with respect to the growth
of the hybridoma by MH166 antibody. MH60.BSF2 cells were dispensed
to 1.times.10.sup.4/200 .mu.l/well, and samples containing MH166
antibody were added thereto, cultured for 48 hours, 0.5 .mu.Ci/well
of .sup.3H-thymidine (New England Nuclear, Boston, Mass.) was
added, and the culturing was continued for further 6 hours. The
cells were placed on a glass filter paper and were treated by the
automatic harvester (Labo Mash Science Co., Tokyo, Japan). As the
control, rabbit anti-IL-6 antibody was used.
[0158] As a result, MH166 antibody inhibited, in a dose dependent
manner, the incorporation of .sup.3H-thymidine of MH60.BSF2 cells
induced by IL-6. This revealed that MH166 antibody neutralizes the
activity of IL-6.
Reference Example 3
Preparation of Human Anti-IL-6 Receptor Antibody
[0159] Anti-IL-6 receptor antibody MT18 prepared by the method of
Hirata et al. (Hirata, Y. et al. J. Immunol., (1989) 143,
2900-2906) was bound to CNBr-activated Sepharose 4B (manufactured
by Pharmacia Fine Chemicals, Piscataway, N.J.) according to the
attached regimen, and IL-6 receptor (Yamasaki, K. et al., Science
(1988) 241, 825-828) was purified. A human myeloma cell line U266
was solubilized with 1 mM p-para-aminophenyl methane sulfonyl
fluoride hydrochloride (manufactured by Wako Chemicals) (digitonin
buffer) containing 1% digitonin (manufactured by Wako Chemicals),
10 mM triethanolamine (pH 7.8) and 0.15 M NaCl and mixed with MT18
antibody bound to Sepharose 4B beads. Then, the beads were washed
six times with the digitonin buffer to prepare the partially
purified IL-6 receptor to be used for immunization.
[0160] BALB/c mice were immunized tour times every ten days with
the above partially purified IL-6 receptor obtained from
3.times.10.sup.9 U266 cells, and then a hybridoma was prepared
using a standard method. The hybridoma culture supernatant from the
growth-positive well was tested for its activity of binding to IL-6
receptor according to the method described below. 5.times.10.sup.7
U266 cells were labeled with .sup.35S-methionine (2.5 mCi) and were
solubilized with the above digitonin buffer. The solubilized U266
cells were mixed with a 0.04 ml volume of MT18 antibody bound to
Sepharose 4B beads, and then were washed six times with the
digitonin buffer. .sup.35S-methionine-labeled IL-6 receptor was
eluted with 0.25 ml of the digitonin buffer (pH 3.4) and was
neutralized in 0.025 ml of 1 M Tris (pH 7.4)
[0161] 0.05 ml of the hybridoma culture supernatant was mixed with
0.01 ml of Protein G Sepharose (manufactured by Pharmacia). After
washing, Sepharose was incubated with 0.005 ml .sup.35S-labeled
IL-6 receptor solution prepared as described above. The
immunoprecipitate was analyzed by SDS-PAGE to investigate the
hybridoma culture supernatant that reacts with IL-6 receptor. As a
result, the reaction-positive hybridoma clone PM-1 (FERM BP-2998)
was established. The antibody produced from the hybridoma PM-1 has
a subtype of IgG1.kappa..
[0162] The inhibitory activity of IL-6 binding of the antibody
produced by the hybridoma PM-1 to human IL-6 receptor was studied
using the human myeloma cell line U266. A human recombinant IL-6
was prepared from E. coli (Hirano et al., Immunol. Lett., (1988)
17, 41-45), and was labeled with .sup.125I using the Bolton-Hunter
reagent (New England Nuclear, Boston, Mass.) (Taga, T. et al., J.
Exp. Med. (1987) 166, 967-981).
[0163] 4.times.10.sup.5 U266 cells were cultured with the culture
supernatant of 70% (v/v) hybridoma PM-1 together with 14,000 cpm of
.sup.125I-labeled IL-6 for one hour. Seventy .mu.l of the sample
was layered on 300 .mu.l FCS in a 400 .mu.l microfuge polyethylene
tube. After centrifugation, the radioactivity of the cell was
determined.
[0164] The result revealed that the antibody produced by the
hybridoma PM-1 inhibits the binding of IL-6 to IL-6 receptor.
Reference Example 4
Preparation of Mouse Anti-IL-6 Receptor Antibody
[0165] A monoclonal antibody directed against mouse IL-6 receptor
was prepared according to the method described in Saito, et al., J.
Immunol. (1991) 147, 168-173.
[0166] The CHO cells that produce mouse soluble IL-6 receptor were
cultured in the IMDM culture liquid containing 10% FCS. From the
culture supernatant, mouse soluble IL-6 receptor was purified using
an affinity column in which anti-mouse IL-6 receptor antibody RS12
(see Saito, et al., supra) was fixed to Affigel 10 gel
(manufactured by Biorad).
[0167] The mouse soluble IL-6 receptor (50 .mu.g) thus obtained was
mixed with Freund's complete adjuvant, which was then injected to
the abdomen of Wistar rats. From 2 weeks after the administration,
the animals were boosted with Freund's incomplete adjuvant. On day
45, rat spleen cells were harvested, and about 2.times.10.sup.8
cells thereof were fused with 1.times.10.sup.7 mouse myeloma cells
P3U1 using a 50% PEG1500 (manufactured by Boehringer Mannheim)
according to the conventional method, and then were screened by the
HAT culture medium.
[0168] After the hybridoma culture supernatant was added to the
plate coated with rabbit anti-rat IgG antibody (manufactured by
Cappel), mouse soluble IL-6 receptor was reacted. Subsequently,
using rabbit anti-mouse IL-6 receptor antibody and alkaline
phosphatase-labeled sheep anti-rabbit IgG, hybridomas producing
antibody directed against mouse soluble IL-6 receptor were screened
by ELISA. After antibody production was confirmed, the hybridoma
clones were subscreened twice to obtain a single hybridoma clone.
The clone was designated as MR16-1.
[0169] The neutralizing activity of the antibody produced by the
hybridoma on signal transduction of mouse IL-6 was examined by
.sup.3H-thymidine incorporation using MH60.BSF2 cells (Matsuda, T.
et al., J, Immunol. (1988) 18, 951-956). To a 96-well plate,
MH60.BSF2 cells were prepared at 1.times.10.sup.4 cells/200
.mu.l/well. To the plate were added 10 pg/ml mouse IL-6 and MR16-1
antibody or RS12 antibody at 12.3-1000 ng/ml, and then were
cultured at 37.degree. C. and 5% CO.sub.2 for 44 hours, and then 1
.mu.Ci/well of .sup.3H-thymidine was added. After 4 hours, the
incorporation of .sup.3H-thymidine was measured. As a result,
MR16-1 antibody suppressed the incorporation of .sup.3H-thymidine
by the MH60.BSF2 cells.
[0170] Thus, it was demonstrated that the antibody produced by the
hybridoma MR16-1 (FERM BP-5875) inhibits the binding of IL-6 to
IL-6 receptor.
* * * * *